Risk analysis of coronary bypass surgery after acute myocardial infarction.

BACKGROUND: Current strategies for management of acute myocardial infarction (MI) include thrombolysis, angioplasty, and coronary bypass surgery singly or in combination. This study was designed to identify contemporary risk factors for coronary bypass surgery among patients in this high-risk group. METHODS: Between June 1992 and December 1995, 1181 consecutive patients underwent isolated coronary bypass surgery. Of these, 316 underwent coronary bypass surgery within 21 days of MI. Mean age was 65 years (range, 33 to 87 years), and 73% were male. There were 166 patients with stable angina (group 1), 107 patients with unstable angina requiring intravenous nitroglycerin for a control of ischemia (group 2), 20 patients with angina requiring intraaortic balloon counterpulsation for stabilization (group 3), and 23 patients with severe postinfarction ischemia complicated by cardiogenic shock (group 4). RESULTS: The overall in-hospital mortality rate was 5.1% (16 of 316), which was higher (p < 0.05) than the 2.5% (22 of 865) among patients undergoing coronary bypass surgery without recent myocardial infarction. Mortality increased with severity of clinical preoperative status and was 1.2% in group 1, 3.7% in group 2, 20.0% in group 3, and 26% in group 4. Serious postoperative morbidity occurred in 7.3% of patients. Multivariate logistic regression analysis identified preoperative intraaortic balloon counterpulsation, left ventricular dysfunction, and renal insufficiency as the only independent correlates of mortality. CONCLUSIONS: Coronary bypass surgery can be safely performed in stable patients at any time after acute MI, with an operative mortality similar to elective surgery. Thus, in this era of medical cost containment, there is no apparent indication for prolonged stabilization attempts that delay surgery.

Cost analysis of early extubation after coronary bypass surgery.

BACKGROUND: Although early extubation after coronary bypass surgery has been shown to reduce length of stay, a systematic cost analysis of its economic benefit has not been reported, and previous studies have used hospital charges that are typically confused with actual costs. METHODS: A consecutive series of 690 patients undergoing coronary bypass surgery during a 24-month period were studied to determine the effect of early extubation, defined as removal of the endotracheal tube within 8 hours of arrival to the intensive care unit, on length of stay and hospital costs. Patients in group 2 (n = 362) who underwent coronary bypass surgery in 1995, subsequent to the initiation of an early extubation protocol, were compared with those in group 1 (n = 328) operated on in 1994, before implementation of early extubation. To reflect true hospital resource consumption, only costs (not charges) directly related to patient health core (variable direct cost) were analyzed. RESULTS: Baseline characteristics such as age, gender, previous myocardial infarctions, ejection fraction, reoperations, diabetes, and left main stenosis were similar in both groups. Operative mortality for the entire group was 3.3% and did not differ between the two groups; the incidence of serious morbidity was 10.9% for the entire group. Early extubation was accomplished in 38% of patients in group 2 versus 3% in group 1 (p < 0.001), and postoperative length of stay declined from 9.4 days to 7.7 days (p < 0.01). This was accompanied by a significant (p = 0.001) reduction in variable direct cost per case. CONCLUSIONS: Early extubation after coronary bypass surgery is an effective strategy of reducing length of stay and does not appear to impact on either morbidity or mortality. An additional benefit is significant cost savings realized through accelerated recovery and control of resource use.

Surgical treatment of interrupted aortic arch in infancy with expanded polytetrafluoroethylene grafts: two-year follow-up results.

The interrupted aortic arch complex is an uncommon but highly lethal combination of anomalies. Multiple approaches have been proposed for the surgical treatment of this complex. These include palliative procedures, direct anastomosis of the interrupted segments, interposition grafting with biological or synthetic conduits, and total correction by closure of the atrial and ventricular septal defects with anastomosis of the proximal and distal aortic segments. This communication reports the good clinical results, noted after 2 years of follow-up, in two consecutive patients with type B interrupted aortic arch who underwent operative repair of the interrupted arch with expanded polytetrafluoroethylene (PTFE) grafts and palliative pulmonary artery banding.

Coronary artery bypass grafts: increased flow in the early postoperative period.

The long-term outcome of coronary artery bypass operations is contingent upon the patency of aortocoronary bypass grafts. Flow measurements taken at operation may not truly reflect the capacity of the graft to carry glow because the heart may not have fully recovered from the consequences of ischemic arrest, despite the protective effects of hypothermic cardioplegia. During a three-year period, we observed increases of up to 200% in the flow rate of 8 of 11 saphenous vein grafts in 7 patients who underwent reoperation for bleeding or cardiac tamponade in the early postoperative period. At initial operation, flow rates ranged from 25 ml/min to 130 ml/min (mean value, 66.8 +/- 10.3 ml/min [standard error of the mean]). At reexploration, flow measurements ranged from 0 ml/min (graft clotted) to 260 ml/min (mean value, 110 +/- 22.8 ml/min). This difference was statistically significant (p less than 0.02). This study documents that flow rate measurements in saphenous vein aorotocoronary bypass grafts can increase in the early postoperative period although the exact mechanism by which this occurs is not known.